Re: [PATCH] mm: fix lazy vmap purging (use-after-free error)

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Mon, Feb 23, 2009 at 12:04:01PM -0800, Andrew Morton wrote:
> On Mon, 23 Feb 2009 20:33:51 +0100
> Ingo Molnar <mingo@elte.hu> wrote:
> 
> > > > > Nice work all (btw. if this patch goes in rather than using system_state,
> > > > > then please make the variable __read_mostly).
> > > > 
> > > > Hmmm...  I misread this and made system_state be __read_mostly.  Let
> > > > me know if this is bad, easy to fix if needed.
> > > 
> > > Please don't use system_state.  The whole thing is just bad 
> > > design. It's a global variable, breaks encapsulation, creates 
> > > interactions etc. CS-101 stuff.
> > 
> > ok, i've removed the patch
> 
> Thanks.
> 
> > - Paul, would you mind to re-send 
> > your original flag solution, with it marked __read_mostly and 
> > with the extern declarations put into a suitable header file?
> 
> It would still make sense to mark system_state __read_mostly.
> 
> (That's assuming that __read_mostly makes sense.  I still wanna
> rename it to __pack_all_write_often_variables_into_the_same_cacheline
> and see what happens then)

The patch I just posted retains this change.  ;-)

							Thanx, Paul